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1.
BMC Surg ; 19(1): 141, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601220

RESUMO

BACKGROUND: The outcomes in patients with pancreatic or ampulla tumors remain unsatisfactory, especially with invasion into the hepatic artery (HA) or the superior mesenteric artery (SMA). In this setting, pancreatectomy combined with arterial resection and reconstruction may offer the possibility of an en-block resection with negative margins and acceptable morbidity and mortality. METHODS: A six year retrospective review of pancreatectomies performed at our institution, included 21 patients that underwent a pancreatectomy combined with arterial resection and reconstruction. Arterial reconstruction was performed under an operating microscope. The types of arterial reconstruction included direct anastomosis, arterial transposition, and arterial bypass with a vascular graft. RESULTS: The surgical procedures consisted of 19 pancreaticoduodenectomies and 2 total pancreatectomies. The tumors were located at the pancreatic head (n = 10), whole pancreas (n = 2), distal common bile duct (n = 5), ampulla (n = 2) and retroperitoneum with pancreatic head involvement (n = 2). All operations achieved R0 resection successfully, with no intraoperative complication. Eighteen patients recovered without complications while three patients died from intra-abdominal hemorrhage due to a pancreatic fistula, though notably the bleeding was not at the arterial anastomosis site. All reconstructed arteries showed adequate patency at follow-up. The median postoperative survival was 11.6 months in all the 11 patients with pancreatic adenocarcinoma. CONCLUSION: Pancreatectomy combined with arterial resection and reconstruction is a feasible treatment option. The microsurgical technique is critically important to achieving a successful and patent arterial anastomosis.

2.
Chin Med J (Engl) ; 132(19): 2308-2314, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31567383

RESUMO

BACKGROUND: Patients with Alzheimer disease (AD) and amnesic mild cognitive impairment (aMCI) have deficits in emotion recognition. However, it has not yet been determined whether patients with AD and aMCI also experience difficulty in recognizing the emotions conveyed by music. This study was conducted to investigate whether musical emotion recognition is impaired or retained in patients with AD and aMCI. METHODS: All patients were recruited from the First Affiliated Hospital of Anhui Medical University between March 1, 2015 and January 31, 2017. Using the musical emotion recognition test, patients with AD (n = 16), patients with aMCI (n = 19), and healthy controls (HCs, n = 16) were required to choose one of four emotional labels (happy, sad, peaceful, and fearful) that matched each musical excerpt. Emotion recognition scores in three groups were compared using one-way analysis of variance (ANOVA) test. We also investigated the relationship between the emotion recognition scores and Mini-Mental State Examination (MMSE) using Pearson's correlation analysis test in patients with AD and aMCI. RESULTS: Compared to the HC group, both of the patient groups showed deficits in the recognition of fearful musical emotions (HC: 7.88 ±â€Š1.36; aMCI: 5.05 ±â€Š2.34; AD: 3.69 ±â€Š2.02), with results of a one-way ANOVA confirming a significant main effect of group (F(2,50) = 18.70, P < 0.001). No significant differences were present among the three groups for the happy (F(2,50)=2.57, P = 0.09), peaceful (F(2,50) = 0.38, P = 0.09), or sad (F(2,50) = 2.50, P = 0.09) musical emotions. The recognition of fearful musical emotion was positively associated with general cognition, which was evaluated by MMSE in patients with AD and aMCI (r = 0.578, P < 0.001). The correlations between the MMSE scores and recognition of the remaining emotions were not significant (happy, r = 0.228, P = 0.11; peaceful, r = 0.047, P = 0.74; sad, r = 0.207, P = 0.15). CONCLUSION: This study showed that both patients with AD and aMCI had decreased ability to distinguish fearful emotions, which might be correlated with diminished cognitive function.

4.
Org Lett ; 21(18): 7445-7449, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31502465

RESUMO

A new donor-acceptor Stenhouse adduct based on a N,N,N'-trimethylethylenediamine donor has been reported. An unprecedented isomer has been isolated, and rich conversions between three isomers have been achieved upon visible-light irradiation or base/acid stimuli. The drastic color change associated with structural conversion has been utilized to selectively sense volatile primary amines as well as high-charged hard Lewis acids (Sc3+, Ti4+, Cr3+, and Al3+).

5.
World Neurosurg ; 132: 245-250, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31476466

RESUMO

BACKGROUND: Little literature is available on mechanical thrombus aspiration in acute ischemic stroke with coincident ipsilateral unruptured aneurysm, especially with aneurysm proximal to the occlusion site. In this report, we describe a case of ischemic stroke in a patient with acute occlusion of M1 segment of the middle cerebral artery with coincident ipsilateral internal carotid artery-posterior communicating artery aneurysm who was successfully treated by mechanical clot retrieval using the Sofia (6F) PLUS technique (MicroVention Terumo, Tustin, California, USA). CASE DESCRIPTION: A 52-year-old woman presented at our hospital 6 hours after sudden onset of dysarthria and right limb hemiplegia on waking up in the morning. She was managed using a direct aspiration first pass technique for distal middle cerebral artery mechanical aspiration using the Sofia (6F) PLUS catheter. The thrombus was manually aspirated in 2 minutes, and Thrombolysis in Cerebral Infarction scale 3 flow was restored. Next, LVIS (MicroVention Terumo, Tustin, California, USA) stent-assisted coiling of the aneurysm of the posterior communicating segment of the left internal carotid artery was immediately undertaken. The National Institutes of Health Stroke Scale score was 4 at day 1 and 0 at day 7 postoperatively. No device-related or catheter-related complications occurred. CONCLUSIONS: Ischemic stroke patients with coincident aneurysm are at increased risk of aneurysmal rupture and should be managed with tailored endovascular strategies. Our case shows that a direct aspiration first pass technique using the Sofia (6F) PLUS catheter provides a safe, effective approach for thrombus aspiration in stroke patients.

6.
Chem Commun (Camb) ; 55(78): 11802-11805, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31524901

RESUMO

Introduction of a heteroatom into a fluorophore was carried out for coumarin through a replacement of its bridging oxygen atom with a silicon atom. The maximum-emission wavelength of Si-coumarin (SiC B) bathochromically shifted from 426 nm in cyclohexane to 626 nm in water. The adipogenic differentiation processes in mesenchymal stem cells were monitored using SiC B.

7.
Chemosphere ; 240: 124761, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31546190

RESUMO

The formation and control of haloacetamides (HAcAms) in drinking water have raised high attention due to their high genotoxicity and cytotoxicity, especially the most cytotoxic one, diiodoacetamide (DIAcAm). In this study, the degradation of DIAcAm by UV/chlorination was investigated in terms of degradation kinetics, efficiency, influencing factors, oxidation products and toxicity evaluation. Results revealed that the degradation of DIAcAm by UV/chlorine process followed pseudo-first-order kinetics, and the rate constant between DIAcAm and OH radicals was determined as 2.8 × 109 M-1 s-1. The contribution of Cl to DIAcAm degradation by UV/chlorine oxidation was negligible. Increasing chlorine dosage and decreasing pH significantly promoted the DIAcAm degradation during UV/chlorine oxidation, but the presence of bicarbonate (HCO3-) and natural organic matter (NOM) inhibited it. The mass balance analysis of iodine species was also evaluated during UV/chlorine oxidation of DIAcAm. In this process, with DIAcAm decreasing from 16.0 to 0.8 µM-I in 20 min, IO3-, I- and HOI/I2 increased from 0 to 6.3, 6.1 and 0.5 µM-I, respectively. The increase of CHO cell viability during DIAcAm degradation indicated that the toxicity of DIAcAm could be decreased by chlorination, UV irradiation and UV/chlorine oxidation treatments, in which UV/chlorine oxidation was more effective on toxicity reduction than chlorination and UV irradiation alone.

8.
J Cell Physiol ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31498437

RESUMO

Tight junction is a structural constitution in cell-cell adhesion and play an important role in the maintenance of permeability and integrity of normal epithelial cell barrier. The protein encoded by Claudin 1 (CLDN1), a member of the claudin family, is an integral membrane protein and a component of tight junction strands. CLDN1 has been proved to regulate the proliferation and metastasis of multiple tumors, but little is known about its role in esophageal squamous cell carcinoma (ESCC). Here, we found that CLDN1 was aberrantly increased in ESCC tissues and cell lines, and mainly distributed in the nucleus of tumor cells. Furthermore, we confirmed that CLDN1 promoted the proliferation and metastasis of ESCC by triggering autophagy both in vitro and in vivo. Mechanically, we validated that CLDN1-induced autophagy via increasing Unc-51 like autophagy activating kinase 1 (ULK1) expression through AMP-activated protein kinase (AMPK)/signal transducer and activator of transcription 1 (STAT1) signaling pathway in ESCC cells. Taken together, our findings demonstrated that aberrant expression and distribution of CLDN1 promoted the proliferation and metastasis of esophageal squamous carcinoma by triggering autophagy through AMPK/STAT1/ULK1 signaling pathway.

9.
Appl Opt ; 58(21): 5687-5694, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31503870

RESUMO

The Integrated Laser Communication/Ranging System, which uses a coded signal as the ranging information carrier, is of great importance to the next large-capacity inter-satellite information network. In this paper, a system design with a high-sensitivity feedback-homodyne detection scheme and an asynchronous ranging algorithm is demonstrated with real-time field-programmable gate array-implementation (FPGA). The parallel fast Fourier transformation (FFT) estimation is applied to improve the speed and the range of the wavelength drift tracking, which can handle a dynamic wavelength drift up to 2.4 pm/s (300 MHz/s). Meanwhile, for clock sources with subtle dynamic frequency offset and sufficient stability, the proposed fractional symbol ranging method is proven to achieve millimeter-level measurement accuracy. The designed system is shown to perform well in terms of both laser linewidth tolerance and noise resistance.

10.
Nat Commun ; 10(1): 4136, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31515491

RESUMO

Astroglia play active and diverse roles in modulating neuronal/synaptic functions in the CNS. How these astroglial functions are regulated, especially by neuronal signals, remains largely unknown. Exosomes, a major type of extracellular vesicles (EVs) that originate from endosomal intraluminal vesicles (ILVs), have emerged as a new intercellular communication process. By generating cell-type-specific ILVs/exosome reporter (CD63-GFPf/f) mice and immuno-EM/confocal image analysis, we found that neuronal CD63-GFP+ ILVs are primarily localized in soma and dendrites, but not in axonal terminals in vitro and in vivo. Secreted neuronal exosomes contain a subset of microRNAs (miRs) that is distinct from the miR profile of neurons. These miRs, especially the neuron-specific miR-124-3p, are potentially internalized into astrocytes. MiR-124-3p further up-regulates the predominant glutamate transporter GLT1 by suppressing GLT1-inhibiting miRs. Our findings suggest a previously undescribed neuronal exosomal miR-mediated genetic regulation of astrocyte functions, potentially opening a new frontier in understanding CNS intercellular communication.

11.
Chem Commun (Camb) ; 55(67): 9955-9958, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31364619

RESUMO

A silver nanocluster-based ratiometric fluorescent nanosensor was developed for the determination of ATP in the cerebrospinal fluid of a mouse brain. Using this useful tool with good stability and high selectivity as well as a wide linear detection range, it was found that the ATP concentration in a mouse brain with Alzheimer's disease was 2300-fold higher than that in a normal one.


Assuntos
Trifosfato de Adenosina/líquido cefalorraquidiano , Química Encefálica , DNA/química , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Encéfalo/citologia , Encéfalo/patologia , Córtex Cerebral/química , Hipocampo/química , Camundongos , Conformação de Ácido Nucleico , Prata/química , Espectrometria de Fluorescência/métodos
12.
Anal Chem ; 91(16): 10901-10907, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31362489

RESUMO

Azoreductase (AzoR) is an essential reductive enzyme which is closely associated with the intestinal disease such as ulcerative colitis (UC). To date, only a few fluorescent probes for detecting AzoR activity in bacteria or cells have been constructed successfully. It is still challenging to design fluorescent probes for in situ monitoring AzoR in vivo. In this paper, a near-infrared (NIR) fluorescent probe (Cy-Azo) based on hemicyanine is designed and synthesized. The emission of the probe is located at 735 nm in the NIR region, which is favorable for its application in vivo. In addition, Cy-Azo shows high sensitivity to AzoR activity with 17-fold fluorescence enhancement and is particularly selective to AzoR over other enzymes, ions, and amino acids. Meanwhile, a possible response mechanism (the azo group in Cy-Azo is reduced by AzoR and cleaved resulting in the production of Cy-NH2) was proposed and verified by HPLC, MS, and theory calculation. In addition, based on low cell cytotoxicity, Cy-Azo is successfully applied in visualizing the activity of AzoR in two cell lines (HCT116 and HepG2 cells) and three types of bacteria (E. coli, S. aureus, and P. aeruginosa). In particular, due to its NIR emission, the probe can monitor AzoR activity in acute and chronic UC mice models. To our knowledge this is the first fluorescent probe for detecting AzoR activity in vivo, which can provide much important information for the diagnosis and treatment of UC.

13.
J Chromatogr A ; : 460417, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31416627

RESUMO

The characterization of metabolome for poorly absorptive natural medicines is challenging. Previous identification strategy often relies on nontargeted scanning biological samples from animals administered with natural medicines in a data-dependent acquisition (DDA) mode by LC-MS/MS. Substances that displayed significant increases following drug administration are thus assigned as potential metabolites. The accurate m/z of precursors and the corresponding MS/MS fragment ions are used to match with herbal ingredients and to infer possible metabolic reactions. Nevertheless, the low concentration of these metabolites within complex biological matrices has often hampered the detection. Herein we developed a strategy termed intestinal mucosal metabolome-guided detection (IMMD) to tackle this challenge using ginkgo biloba (GBE) as an example. The rationale is that poorly absorptive natural products are usually concentrated and extensively metabolized by enterocytes before they enter the blood stream and distribute to other organs. Therefore, we firstly identified the metabolites from intestinal mucosa of GBE-treated rats, and then used the identified intestinal mucosal GBE metabolome as targeted repository for MRM analysis. The presences of these metabolites were subsequently examined in rat plasma, liver and brain. The resultant GBE metabolome showed significantly improved coverage with 39, 45 and 6 metabolites identified in plasma, liver and brain compared to 22, 16 and 0 metabolites from the corresponding regions via the DDA-based strategy. In addition, we integrated the previously reported nontargeted diagnostic ion network analysis to facilitate the characterization of GBE components, and a chemicalome-metabolome matching approach (CMMA) to assist the identity assignment of GBE metabolome with IMMD. Combinatorially, we establish a multi-faceted platform to streamline the workflow of metabolome characterization for herbal medicines of low bioavailability. The metabolome information is expected to shed light on the elucidation of metabolic pathways for natural products, and the underlying mechanisms of their biological efficacies.

14.
Chem Commun (Camb) ; 55(73): 10960-10963, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451817

RESUMO

FeSe2-carbon nanotube (FeSe2-CNT) hybrid microspheres are investigated as anode materials for lithium ion batteries (LIBs), exhibiting a high specific capacity of 571.2 mA h g-1 at 0.5 A g-1 with excellent rate performance and cycling stability. The FeSe2-CNT hybrid LIBs could withstand the high-voltage pulse of triboelectric nanogenerators (TENGs) and be charged by TENGs directly for harvesting energy with high stability.

15.
Neurosci Bull ; 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31388929

RESUMO

The current study was designed to explore how disruption of specific molecular circuits in the cerebral cortex may cause sensorimotor cortico-striatal community structure deficits in both a mouse model and patients with schizophrenia. We used prepulse inhibition (PPI) and brain structural and diffusion MRI scans in 23 mice with conditional ErbB4 knockout in parvalbumin interneurons and 27 matched controls. Quantitative real-time PCR was used to assess the differential levels of GABA-related transcripts in brain regions. Concurrently, we measured structural and diffusion MRI and the cumulative contribution of risk alleles in the GABA pathway genes in first-episode treatment-naïve schizophrenic patients (n = 117) and in age- and sex-matched healthy controls (n = 86). We present the first evidence of gray and white matter impairment of right sensorimotor cortico-striatal networks and reproduced the sensorimotor gating deficit in a mouse model of schizophrenia. Significant correlations between gray matter volumes (GMVs) in the somatosensory cortex and PPI as well as glutamate decarboxylase 1 mRNA expression were found in controls but not in knockout mice. Furthermore, these findings were confirmed in a human sample in which we found significantly decreased gray and white matter in sensorimotor cortico-striatal networks in schizophrenic patients. The psychiatric risk alleles of the GABA pathway also displayed a significant negative correlation with the GMVs of the somatosensory cortex in patients. Our study identified that ErbB4 ablation in parvalbumin interneurons induced GABAergic dysregulation, providing valuable mechanistic insights into the sensorimotor cortico-striatal community structure deficits associated with schizophrenia.

16.
World J Gastroenterol ; 25(27): 3527-3537, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31367154

RESUMO

Hepatitis B virus (HBV) infection is one the leading risk factors for chronic hepatitis, liver fibrosis, cirrhosis and hepatocellular cancer (HCC), which are a major global health problem. A large number of clinical studies have shown that chronic HBV persistent infection causes the dysfunction of innate and adaptive immune response involving monocytes/macrophages, dendritic cells, natural killer (NK) cells, T cells. Among these immune cells, cell subsets with suppressive features have been recognized such as myeloid derived suppressive cells(MDSC), NK-reg, T-reg, which represent a critical regulatory system during liver fibrogenesis or tumourigenesis. However, the mechanisms that link HBV-induced immune dysfunction and HBV-related liver diseases are not understood. In this review we summarize the recent studies on innate and adaptive immune cell dysfunction in chronic HBV infection, liver fibrosis, cirrhosis, and HCC, and further discuss the potential mechanism of HBV-induced immunosuppressive cascade in HBV infection and consequences. It is hoped that this article will help ongoing research about the pathogenesis of HBV-related hepatic fibrosis and HBV-related HCC.

17.
ISA Trans ; 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31399252

RESUMO

A new approach to gait rehabilitation task of a 12 DOF lower limb exoskeleton is proposed combining time-delay estimation (TDE) based computed torque control (CTC) and robust adaptive RBF neural networks. In addition to the conventional advantages of the CTC, TDE technique is integrated to estimate unmodeled dynamics and external disturbance. To realize more accurate tracking, a robust adaptive RBF neural networks compensator is designed to approximate and compensate TDE error. The final asymptotic stability is guaranteed with Lyapunov criteria. To validate the proposed approach, co-simulation experiments are realized using SolidWorks, SimMechanics and MATLAB/Robotics Toolbox. Compared to CTC, sliding mode based CTC and TDE based CTC, the higher performances of the proposed controller are demonstrated by co-simulation.

18.
Artigo em Inglês | MEDLINE | ID: mdl-31392819

RESUMO

Pathogen detection is growing in importance in the global health arena because of the high morbidity and mortality associated with bacterial blood stream infections. In this work, we present stochastic DNA walkers in droplets (SDwalker-Drop), a one-step, rapid, and super-multiplex method for ultrahigh-throughput bacterial detection. The SDwalkers, by exploiting cascade signal amplification, endow our analytical platform with fast analysis times and single-cell analysis ability. The autonomous and multiple-step walking behavior of the SDwalkers provides a super-multiplex droplet-encoding strategy by embedding intensity coded barcodes into a sequence of color-multiplexed barcodes. We realized a theoretical coding capacity of 83 -1=511 and achieved 20 distinct patterns for bacterial phenotype detection and identification. Moreover, our SDwalker-Drop platform could be readily integrated with a flow cytometer to afford a general approach for super-multiplexed, high-throughput biological assays and screening.

19.
Compr Psychiatry ; 94: 152114, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31401216

RESUMO

BACKGROUND: Promising biomarkers would be used to improve the determination of diagnosis and severity, as well as the prediction of symptomatic and functional outcomes of schizophrenia. BASIC PROCEDURES: In this study, we used three different mouse models induced by a genetic factor (PV-Cre; ErbB4-/-, G group), an environmental stressor (adolescent social isolation, G group), and a combination of genetic factor and environmental stressor (PV-Cre; ErbB4-/- mice with isolation, G × E group). Attenuated PPI (%) confirmed the successful establishment of three schizophrenia-like mouse models. To evaluate whether neuropeptide levels in plasma would be potential biomarkers of different schizophrenia models in our work, we used MILLIPLEX® MAP method to simultaneously measure 6 critical neuropeptides in plasma. MAIN FINDINGS: Among the evaluated neuropeptides, increased neurotensin tends to be associated with genetic factors of schizophrenia, increased orexin A seems to be a biomarker of an interplay between genetic and social isolation, while higher plasma oxytocin might be more apt to be responsive to social isolation. The potential biomarkers are mostly independent of sex. CONCLUSIONS: This research would provide novel clues to develop circulating biomarkers of plasma neuropeptides for multifactorial schizophrenia.

20.
Fish Physiol Biochem ; 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31325080

RESUMO

CDK-2, a member of the cyclin-dependent kinase family, plays an important role in many cell processes, such as cell cycle regulation, cell growth and differentiation, and cell apoptosis. Lampreys belong to the most primitive vertebrates, and there is no report about the CDK-2 gene in lampreys at present. In this study, a CDK-2-like gene sequence and deduced amino acid sequence were identified in Japanese lamprey (Lampetra japonica, L. japonica). The CDK-2-like gene has about 80% similarity with its homologs in jaw vertebrates. The polyclonal antibody against CDK-2-like was well prepared, and the results showed that CDK-2-like was highly expressed in the gonad tissue of lampreys. Apoptosis could reduce the expression of CDK-2-like in lymphocytes of lamprey, while overexpression of CDK-2-like could inhibit apoptosis. In addition, inhibition of CDK-2-like activity was able to trigger out apoptosis and also helped apoptotic inducer actinomycin D (Act-D) to induce apoptosis. These results suggest that CDK-2-like identified from lamprey may play a crucial role in apoptosis of jawless vertebrates.

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